[ECO code B01]
The Collijn Variation
Black develops his Queen's Bishop to KKt5(g4) to pin White's Kt+Q. The Swedish Collijn brothers produced many books on 19th/20th century Scandinavian tournaments. B-Alt.
White Black White Black 1. P-K4 P-Q4 5. Kt-B3 B-KKt5 2. PxP QxP 3. Kt-QB3 Q-QR4 4. P-Q4 P-K4
Example ends: Undo or Jump or Clear